(a) Technical Field
The present disclosure relates to a battery module capable of maintaining contact with other battery packs connected in series except for the failed battery packs when some battery packs are failed.
(b) Description of the Related Art
Generally, a battery module of a large capacity mounted to a vehicle, for example, has been used in which a plurality of battery packs are coupled in series. However, each respective battery pack has a slight difference in its durability life due to manufacturing allowances, and further the battery packs are deteriorated or worn out separately in accordance with driving conditions.
In conventional lithium ion secondary batteries or a battery pack thereof, a physical power cut off principle using volume inflation by swelling is applied in order to ensure safety in case of a short circuit and over-charging.
As a representative example of a battery module, in Korean Publication No. 10-0914839, it is disclosed that a middle-large battery pack includes: a battery module of a high output and a large capacity in which a plurality of battery cells or unit modules are connected in series in a lamination state where they are in close contact or adjacent each other, the battery module is fixed to maintain the lamination state of the battery cells or the unit modules even when the battery module varies in their volumes while charging/discharging the battery, and further a part of a coupling portion of the electrode terminals is formed with a fragile structure so that the coupling portion of electrode terminal is ruptured to cut off power when inflation stress caused from a swelling of a battery cell is concentrated on the coupling portion of electrode terminals of the battery cells or the unit modules and the swelling value becomes a predetermined value or more; a battery management system (BMS) for detecting an operation state and controlling it; and a power cut off portion that is disposed between the battery module and an external input-output circuit and connects them in accordance with an operation order from the BMS wherein the plurality of battery modules are fixed by a frame member, outermost battery modules are surrounded by a sealing member fixed to the frame member, and a cutting portion or a notch portion shaped for inducing partial deformation of a swelling battery module is formed on a portion of the sealing member adjacent to the coupling portion of the electrode terminal such that the battery modules are shut off from the power cut off portion independently from the BMS in an abnormal operation condition.
However, according to the related art as described above, since the physical power cut off is induced, a battery system operation stops, and thus it is possible that another risk such as a collision may be caused as the result of an unexpected vehicle stop during driving.
When an auxiliary unit for ensuring additional safety for a vehicle is designed, it is preferred that a battery system can be operated constantly by bypassing an abnormal battery cell and using a normal battery cell, with a pressure switch for sensing gas generation due to swelling conditions of the respective battery cells being mounted to the battery system. Through such an improved configuration, even when the battery system has its power cut off while a vehicle is driven, a secondary collision that may be caused from a vehicle stop before a driver takes an action in advance can be prevented.
The description provided above as a related art of the present invention is just for helping understanding the background of the present invention and should not be construed as being included in the related art known by those skilled in the art.